No Quarter Given: The Obsidian Sanctum: Sartharion Boss Strategy, 10-Man

The Obsidian Sanctum: Sartharion Boss Strategy, 10-Man Zug Gaming

Here's the link to the guide I found but I've included all the information below:

The Obsidian Sanctum is single boss instance located underneath Wyrmrest Temple in central Dragonblight. The instance features Sartharion as the primary boss with the addition of trash mobs and 3 other min-bosses. The other mini-bosses aka Drakes may be killed or left up. The more drakes you kill the easier Sartharion is to defeat, however, leaving additional drakes up will provide you with better loot.
Each drake left alive provides Sartharion with additional abilities, which will add difficulty to the encounter.
For beginners I highly suggest you learn the fight with zero drakes alive, once you’re comfortable with this strategy you could move onto to the more difficult encounters of leaving several drakes up.
The Obsidian Sanctum Strategy
Mini-Drake Bosses
Let’s start with the mini-drake bosses. These “bosses” are very simple, the only real mechanic involves the summoning of a phase portal. Inside this portal are drake eggs and / or dragonkin. You should send approximately half your raid through the portal to deal with these mobs. Failure to kill some / most of the mobs in the portal will result in negative action on the non-portal side…IE, more stuff is going to spawn and you’ll likely die.
Beyond that all 3 of the mini-drakes are a general tank and spank fight. Just be aware of the patrols of other elite dragonkin that walk around the drakes.
Sartharion Boss Strategy
Killing Sartharion with 0 Drakes Alive
For this first strategy let’s go over the strategy with zero drakes alive. There really are only 2 mechanics to this boss fight.
Lava Wave
Fire Elemental Adds
The lava wave is spawns on 2 sides, left and right. The location of this spawn determines the location of the gap in the wave. Your raid will need to adjust their position to fit into this gap as it passes over, thus avoiding fire damage and a knock into the lava. Just be aware of the wave spawn and you’ll easily make it through the gap.
The fire elemental adds are also fairly straight forward. Adds will spawn throughout the fight, these should be picked up by the off tank and immediately killed by DPS players.

Sartharion Video Boss Strategy:

This is the main boss with all drakes dead.